JOB RUN: 'Full OnlineLogging' was run on 9/13/2010 at 3:03:52 AMDURATION: 0 hours, 0 minutes, 0 secondsSTATUS: FailedMESSAGES: The job failed. The Job was invoked by User name The last step to run was step 1 (execute master..sqlbackup). The job was requested to start at step 1 (execute master..sqlbackup).

As Dave alluded to with his Google search, the problem is that you're trying to overwrite a file with the same name. If you take a look at the below link and search for error code 510, you'll see the definition of the error: